Go-Toba

Go-Toba (6 August 1180-28 March 1239), also called Toba II, was the 82nd Emperor of Japan, reigning from 1183 until his deposition by the Kamakura Minamoto. Under his reign, the Heian Empire of Japan saw the end of the Genpei War and the start of a new era of warfare: the Kenkyu War.

Biography
Go-Toba was the son of Emperor Takakura and his wife Fujiwara Ninshi, and he was thus partially of Fujiwara clan lineage. When the Taira were forced from Kyoto by the Minamoto, he was made the Emperor by the Kamakura Minamoto, who took over Japan by 1188. Go-Toba succeeded Emperor Antoku, and after Antoku's death in 1185 by drowning in the Battle of Dan-no-Ura, not only did the Genpei War end, but Go-Toba was now fully-independent from any regnal disputes.

He was domineered by Minamoto Yoritomo, who was the leader of the Kamakura Minamoto family. In 1190 the imperial family, oppressed and weak, declared the Minamoto enemies of the state and many of the Minamoto clan's vassals and allies rebelled and betrayed the Kamakura Minamoto. Go-Toba had little authority, as he was only ten years old when his family declared the Minamoto to be traitors. He heralded a new era of warfare, as the Kenkyu War broke out: it was named for the Kenkyu Era (1190-1199).